package com.helloweenvsfei.filter;import java.io.IOException;import javax.servlet.Filter;import javax.servlet.FilterChain;import javax.servlet.FilterConfig;import javax.servlet.ServletException;import javax.servlet.ServletRequest;import javax.servlet.ServletResponse;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.apache.commons.logging.Log;import org.apache.commons.logging.LogFactory;public class LogFilter implements Filter {    private Log log = LogFactory.getLog(this.getClass());    private String filterName;    public void init(FilterConfig config) throws ServletException {        // 获取 Filter 的 name，配置在 web.xml 中        filterName = config.getFilterName();        log.info("启动 Filter: " + filterName);    }    public void doFilter(ServletRequest req, ServletResponse res,            FilterChain chain) throws IOException, ServletException {        HttpServletRequest request = (HttpServletRequest) req;        HttpServletResponse response = (HttpServletResponse) res;        long startTime = System.currentTimeMillis();        String requestURI = request.getRequestURI();        requestURI = request.getQueryString() == null ? requestURI                : (requestURI + "?" + request.getQueryString());        chain.doFilter(request, response);        long endTime = System.currentTimeMillis();        log.info(request.getRemoteAddr() + " 访问了 " + requestURI + ", 总用时 "                + (endTime - startTime) + " 毫秒。");    }    public void destroy() {        log.info("关闭 Filter: " + filterName);    }}

log4j.rootLogger=INFO, A1log4j.appender.A1=org.apache.log4j.ConsoleAppenderlog4j.appender.A1.layout=org.apache.log4j.PatternLayoutlog4j.appender.A1.layout.ConversionPattern=%-d{yyyy-MM-dd HH\:mm\:ss,SSS} [%l]-[%p] %m%n

<filter>    <filter-name>logFilter</filter-name>    <filter-class>com.helloweenvsfei.filter.LogFilter</filter-class></filter><filter-mapping>    <filter-name>logFilter</filter-name>    <url-pattern>/*</url-pattern></filter-mapping>